| 1 | Confirm the fire-resistance requirement | Review the required operating temperature, exposure duration, airflow direction, and applicable local safety standards. | Low to moderate when the fan is correctly selected and installed. | A correctly sized fan avoids unnecessary oversizing and wasted electricity. | Documented test results, traceable materials, and clearly stated temperature limits. | Do not treat a standard ventilation fan as fire resistant without verified test documentation. |
| 2 | Match airflow and static pressure | Compare the required airflow, measured in m³/h or CFM, with the system’s total duct resistance and pressure drop. | Inspect ducts, grilles, dampers, and bearings at least annually; dusty systems may need more frequent cleaning. | Operating near the duty point generally reduces throttling losses and excessive motor load. | Stable airflow without abnormal vibration, overheating, or repeated overload trips. | Use a fan curve rather than comparing airflow capacity alone. |
| 3 | Evaluate motor efficiency and controls | Check motor input power, duty cycle, speed control compatibility, and whether variable-speed operation is permitted for the application. | Electrical connections and control settings should typically be checked annually. | Variable-speed control can reduce energy use when full airflow is not always required; savings depend on the system curve and operating schedule. | A motor that runs within its rated load and temperature range is less likely to suffer premature failure. | Compare kW at the required operating point, not only the motor’s maximum rating. |
| 4 | Choose serviceable construction | Look for accessible inspection panels, replaceable bearings where appropriate, corrosion-resistant surfaces, and standard fasteners. | Routine cleaning and visual inspection are usually easier when internal components are accessible. | Efficient maintenance helps preserve fan balance and airflow, preventing energy increases caused by fouling. | Replaceable wear parts and accessible components can extend useful service life and reduce downtime. | Avoid designs that require complete removal of the fan for basic inspection. |
| 5 | Consider the installation environment | Assess smoke, grease, moisture, corrosive gases, dust concentration, ambient temperature, and outdoor exposure. | Grease- or dust-laden environments may require cleaning monthly or quarterly, depending on contamination levels. | Blocked filters, coated blades, and restricted ducts increase pressure drop and power consumption. | Correct material protection and environmental suitability help prevent corrosion, imbalance, and insulation damage. | Select enclosure, coating, seals, and electrical protection according to the actual environment. |
| 6 | Plan inspection and testing | Establish checks for airflow, vibration, bearing noise, motor temperature, electrical current, alarms, and emergency operation. | Basic visual checks can be monthly; functional and electrical testing is commonly scheduled at least annually, subject to local rules. | Trend monitoring can identify fouling or mechanical problems before they cause higher power consumption. | Recorded test trends provide early warning of bearing wear, imbalance, or motor deterioration. | Keep inspection records and follow the applicable building and fire-safety maintenance schedule. |
| 7 | Compare total cost of ownership | Include purchase price, installation, controls, spare parts, electricity, inspections, downtime, and expected replacement needs. | Lower-cost units may require more frequent cleaning or have less convenient access to service parts. | Annual energy cost depends on input power, operating hours, electricity price, and actual load. | Long-term value is better indicated by service history, parts availability, stable performance, and documented testing. | Use a multi-year lifecycle comparison instead of choosing solely by initial purchase price. |